Chuck for holding a device under test

1. A chuck for a probe station comprising: (a) a first chuck assembly element having an upper surface thereon suitable to support a wafer; (b) a chuck spacing mechanism connected to said first chuck assembly element having exactly three independent supports defining the spacing between said first chuck assembly element and another chuck assembly element, each said support proximate said another chuck assembly element; and (c) a stabilizing member operatively engaged with at least one of said supports at a location at least partially between said first chuck assembly element and said another chuck assembly element, said stabilizing member inhibiting lateral movement of said first chuck assembly element with respect to said another chuck assembly element.

2. The chuck of claim 1 wherein said chuck spacing mechanism maintain said first chuck assembly element and said another chuck assembly element in a rigid relationship with respect to each other.

3. The chuck of claim 1 wherein each of said supports are substantially equal distant from one another.

4. The chuck of claim 1 wherein each of said supports is free from directly electrically interconnecting said first chuck assembly element and said another chuck assembly element.

5. The chuck of claim 1 wherein said first chuck assembly element is electrically connected to a signal path.

6. The chuck of claim 5 wherein said another chuck assembly element is electrically connected to a guard path.

7. The chuck of claim 1 further comprising: (a) said first chuck assembly element having a lower surface, said first chuck assembly element defining at least one first air path therein to said upper surface; (b) said another chuck assembly element having an upper surface in opposing relationship to said lower surface of said first chuck assembly element, said second chuck assembly defining at least one second air path therein; and (c) an interconnecting member interconnecting said first air path and said second air path in such a manner that a vacuum may be provided from said first air path to said second air path, said interconnecting member movable with respect to at least one of said first chuck assembly element and said second chuck assembly element.

8. The chuck of claim 1 further comprising: (a) said first chuck assembly element having a lower surface defining at least one recess therein; and (b) a cover plate in overlying relationship to said lower surface of said first chuck assembly element together defining at least a portion of an air path to said upper surface suitable for providing a vacuum to said wafer supported by said upper surface.

9. The chuck of claim 1 comprising: (a) a first chuck assembly element having a lower surface, said first chuck assembly element defining at least one first air path therein to said upper surface; (b) said another chuck assembly element having an upper surface in opposing relationship to said lower surface of said first chuck assembly element, said second chuck assembly defining at least one second air path therein; and (c) an interconnecting member interconnecting said first air path and said second air path in such a manner that a vacuum may be provided from said first air path to said second air path.

10. The chuck of claim 9 wherein said interconnecting member is located closer the periphery of said first chuck assembly element than a nearest member determining, at least in part, the spacing between said first chuck assembly element and said another chuck assembly element.

11. The chuck of claim 1 comprising: (a) said first chuck assembly element having a lower surface; (b) said another chuck assembly element having an upper surface and a lower surface where the upper surface is in opposing relationship to said lower surface of said first chuck assembly element; and (c) a cover plate in overlying relationship to at least a major portion of said lower surface of said another chuck assembly element proximate said chuck spacing mechanism element.

12. The chuck of claim 1 comprising: (a) said first chuck assembly element having a lower surface; (b) said another chuck assembly element having an upper surface and a lower surface where the upper surface is in opposing relationship to said lower surface of said first chuck assembly element; and (c) at least one of said supports including an insulator having a first surface and a second surface surrounding at least a portion of said at least one supports between the upper and lower surfaces of said another chuck assembly element, at least a first portion of a first surface of said insulator in pressing engagement with said another chuck assembly element, at least a second portion of a second surface of said insulator in pressing engagement with said at least one support.

13. The chuck of claim 1 wherein said first portion of said first surface and said second portion of said second surface have an overlapping relationship over at least a major portion of at least one of said first portion and said second portion.

14. The chuck of claim 1 comprising: (a) said first chuck assembly element having a lower surface; (b) said another chuck assembly element having an upper surface and a lower surface where the upper surface is in opposing relationship to said lower surface of said first chuck assembly element; and (c) at least one of said supports including a generally U-shaped insulator having a first surface in pressing engagement with said upper surface of said another chuck assembly element and a second surface in pressing engagement with a first surface of a generally U-shaped conductive spacer, a second surface of said U-shaped conductive spacer in pressing engagement with said lower surface of said first chuck assembly element.

15. The chuck of claim 1 comprising: (a) said first chuck assembly element having a lower surface; (b) said another chuck assembly element having an upper surface and a lower surface where the upper surface is in opposing relationship to said lower surface of said first chuck assembly element; (c) a chuck spacing mechanism interconnecting said first and second chuck assembly elements and defining the spacing between said first and second chuck assembly elements; and (d) at least one of said supports including an insulator having a first surface in pressing engagement with said upper surface of said another chuck assembly element and a second surface in pressing engagement with a first surface of a conductive spacer, a second surface of said conductive spacer in pressing engagement with said lower surface of said first chuck assembly element, where said first surface of said insulator in pressing engagement with said upper surface is substantially directly opposing and coextensive with said second surface of said insulator in pressing engagement with said conductive spacer.

16. The chuck of claim 1 further comprising: (a) said first chuck assembly element having a lower surface; (b) said another chuck assembly element having an upper surface and a lower surface where the upper surface is in opposing relationship to said lower surface of said first chuck assembly element; and (c) said chuck spacing mechanism including an insulator having a first surface in pressing engagement with said upper surface of said another chuck assembly element and a second surface in pressing engagement with a first surface of a conductive spacer, a second surface of said conductive spacer in pressing engagement with said lower surface of said first chuck assembly element, where said first surface of said insulator in pressing engagement with said upper surface is less than one third the thickness of said conductive spacer in pressing engagement with said second surface.